Low voltage and dying battery


tevan
ICOA Member
ICOA Member
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Location: Charleston, Illinois, USA
Location: Charleston, Illinois, USA

Re: Low voltage and dying battery

Post by tevan »

tevan wrote:I would have battery checked. Just because you have 12.5 volts doesn’t mean you have the amperage. I would take the battery and get it load tested.
That is what I said to start with. Then go from there.

daves79x
ICOA Technical Director
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Location: Knox, PA

Re: Low voltage and dying battery

Post by daves79x »

Which is why I get increasingly frustrated answering questions and offering suggestions. Why do guys ask if they don't trust our opinions? Carry on.

Dave

Playtex11

Re: Low voltage and dying battery

Post by Playtex11 »

Sorry Dave. All guidance and suggestions received here are very much appreciated. You have to realize that not all on this board may have your level of expertise and seeking to frustrate those who furnish guidance was certainly not my aim.

When I got home yesterday, I took it off the trickle charger and measured the YUASA at 13.03 volts with the key off. Turned it on and it spun the starter very well and touched right off. Voltage dropped to only 11 during the start. At 3000 RPM, The red output wire from the alt showed 14.3 volts and the black wire showed 15.05 volts. Battery voltage at the terminals was 14.9. Sounding pretty good? Didn't work out that way. After a 20 minute run, the lights became dimmer and the signals were slower in flashing. It died as I was parking it (thankfully it made it home). Key on voltage check on battery at that time was 7 volts. It is getting a battery tomorrow and both batteries involved (YUASA and Odyssey) will get load checks at the shop. Will post results.

Playtex11

Re: Low voltage and dying battery

Post by Playtex11 »

OK, both batteries (Odyssey and YUASA) tested bad. I bought a MOTOCROSS brand AGM type replacement for the bike. MOTOCROSS is owned by YUASA so they are identical except for the label.
Installed it and took the following readings at the battery terminals
with an independent multi meter:
Key off-12.78 v
Key on- 11.94v
Starter on-10.9v
Idle 1100 RPM-12.35v
1500RPM-13.4v
3000RPM15.1v
3000RPM with
55w driving lights on- 15.04v

Alternator wire tests:
Idle RPM Black Wire-12v
Red wire-11.27v
3000RPM Black 14.27v
Red 15.1v

This has been a long thread and I thank all involved for their patience with me.
For lessons learned, listen to those who know (tevan, Larrry, Steve, wyly, ems, desert refugee,daves79x and hondaman160).
I am guessing the battery ruined the alternator and the repaired alternator could not sustain the crippled battery.

Thanks again guys!

Larry Zimmer
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Location: Brighton, Mich
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Re: Low voltage and dying battery

Post by Larry Zimmer »

From this, I'm thinking 'problem solved'. Great. Now, for some riding fun!!
Larry Zimmer
cbxlarry@sbcglobal.net

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